2003 GMC SONOMA maintenance

4. Reapply the regular brakes. Then apply your
parking brake, and then shift into PARK (P),
or REVERSE (R) for a manual transmission.
5. If you have a four-wheel-drive vehicle with an
automatic transfer case, be sure the transfer case
is in a drive gear–not in NEUTRAL.
6. Release the regular brakes.
When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
start your engine,
shift into a gear, and
release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the
chocks.
Maintenance When Trailer Towing
Your vehicle will need service more often when you’re
pulling a trailer. SeePart A: Scheduled Maintenance
Services on page 6-4for more on this. Things that are
especially important in trailer operation are automatic
transmissionuid (don’t overll), engine oil, axle
lubricant, belt, cooling system and brake system.
Each of these is covered in this manual, and the Index
will help yound them quickly. If you’re trailering,
it’s a good idea to review these sections before you
start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
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Windshield Wiper Blade Replacement..............5-56
Tires..............................................................5-58
Inflation–Tire Pressure................................5-58
Tire Inspection and Rotation...........................5-60
When It Is Time for New Tires.......................5-61
Buying New Tires.........................................5-62
Uniform Tire Quality Grading..........................5-63
Wheel Alignment and Tire Balance..................5-64
Wheel Replacement......................................5-65
Tire Chains..................................................5-66
If a Tire Goes Flat........................................5-67
Changing a Flat Tire.....................................5-68
Compact Spare Tire......................................5-78
Appearance Care............................................5-79
Cleaning the Inside of Your Vehicle.................5-79
Care of Safety Belts......................................5-82
Weatherstrips...............................................5-82
Cleaning the Outside of Your Vehicle..............5-82Sheet Metal Damage.....................................5-85
Finish Damage.............................................5-85
Underbody Maintenance................................5-85
Chemical Paint Spotting.................................5-85
GM Vehicle Care/Appearance Materials...........5-86
Vehicle Identification......................................5-87
Vehicle Identification Number (VIN).................5-87
Service Parts Identification Label.....................5-88
Electrical System............................................5-88
Add-On Electrical Equipment..........................5-88
Headlamps..................................................5-88
Windshield Wiper Fuses................................5-88
Power Windows and Other Power Options.......5-88
Fuses and Circuit Breakers
............................5-89
Capacities and Specifications
..........................5-94
Capacities and Specifications
.........................5-95
Normal Maintenance Replacement Parts
..........5-96
Section 5 Service and Appearance Care
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Service
Your dealer knows your vehicle best and wants you to
be happy with it. We hope you’ll go to your dealer
for all your service needs. You’ll get genuine GM parts
and GM-trained and supported service people.
We hope you’ll want to keep your GM vehicle all GM.
Genuine GM parts have one of these marks:
Doing Your Own Service Work
If you want to do some of your own service work, you’ll
want to use the proper service manual. It tells you much
more about how to service your vehicle than this manual
can. To order the proper service manual, seeService
Publications Ordering Information on page 7-9.
Your vehicle may have an air bag system. If it does, see
Servicing Your Air Bag-Equipped Vehicle on page 1-63
before attempting to do your own service work.
You should keep a record with all parts receipts and list
the mileage and the date of any service work you
perform. SeePart E: Maintenance Record on page 6-35.
{CAUTION:
You can be injured and your vehicle could be
damaged ifyou try to do service work on a
vehicle without knowing enough about it.
•Be sure you have sufficient knowledge,
experience, the proper replacement parts
and tools before you attempt any vehicle
maintenance task.
CAUTION: (Continued)
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Engine Oil Additives
Don’t add anything to your oil. The recommended oils
with the starburst symbol are all you will need for
good performance and engine protection.
When to Change Engine Oil
If any one of these is true for you, use the short trip/city
maintenance schedule:
•Most trips are less than 5 miles (8 km). This is
particularly important when outside temperatures
are below freezing.
•Most trips include extensive idling (such as
frequent driving in stop-and-go traffic).
•You frequently tow a trailer or use a carrier on
top of your vehicle.
•The vehicle is used for delivery service, police,
taxi or other commercial application.Driving under these conditions causes engine oil to
break down sooner. If any one of these is true for your
vehicle, then you need to change your oil andfilter
every 3,000 miles (5 000 km) or 3 months—whichever
occursfirst.
If none of them is true, use the long trip/highway
maintenance schedule. Change the oil andfilter every
7,500 miles (12 500 km) or 12 months—whichever
occursfirst. Driving a vehicle with a fully warmed engine
under highway conditions will cause engine oil to
break down slower.
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When to Inspect the Engine Air
Cleaner/Filter
Inspect the air cleaner/filter every 15,000 miles
(25 000 km) and replace every 30,000 miles (50 000 km).
If you are driving in dusty/dirty conditions, inspect the
filter at each engine oil change.
How to Inspect the Engine Air
Cleaner/Filter
To remove either engine air cleaner/filter, do the
following:
1. Remove the fasteners that hold the cover on and
remove the cover
2. Lift out the engine air cleaner/filter, if needed.
3. Insert a new airfilter. SeeNormal Maintenance
Replacement Parts on page 5-96to determine
whichfilter to use.
4. Reinstall the engine air cleaner/filter cover.
Tighten the fasteners to hold the cover in place.
{CAUTION:
Operating the engine with the air cleaner/lter
off can cause you or others to be burned. The
air cleaner not only cleans the air, it helps to
stopame if the engine backres. If it isn’t there
and the engine backres, you could be burned.
Don’t drive with it off, and be careful working on
the engine with the air cleaner/lter off.
Notice:If the air cleaner/lter is off, a backre can
cause a damaging enginere. And, dirt can
easily get into your engine, which will damage it.
Always have the air cleaner/lter in place when
you’re driving.
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Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmissionfluid
level is when the engine oil is changed.
Change both thefluid andfilter every 15,000 miles
(25 000 km) if the vehicle is mainly driven under one
or more of these conditions:
•In heavy city traffic where the outside temperature
regularly reaches 90°F (32°C) or higher.
•In hilly or mountainous terrain.
•When doing frequent trailer towing.
•Uses such as found in taxi, police or delivery
service.
If you do not use your vehicle under any of these
conditions, change thefluid andfilter every
50,000 miles (83 000 km).
SeePart A: Scheduled Maintenance Services
on page 6-4.
How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership service
department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
Notice:Too much or too littleuid can damage
your transmission. Too much can mean that some
of theuid could come out and fall on hot engine
part or exhaust system parts, starting are.
Too littleuid could cause the transmission to
overheat. Be sure to get an accurate reading if you
check your transmissionuid.
Wait at least 30 minutes before checking the
transmissionfluid level if you have been driving:
•When outside temperatures are above 90°F (32°C).
•At high speed for quite a while.
•In heavy traffic–especially in hot weather.
•While pulling a trailer.
To get the right reading, thefluid should be at normal
operating temperature, which is 180°Fto200°F
(82°Cto93°C)
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3. Check both sides of the dipstick, and read the lower
level. Thefluid level must be in the COLD area,
below the cross-hatched area, for a cold check or in
the HOT area or cross-hatched area for a hot
check.
4. If thefluid level is in the acceptable range, push the
dipstick back in all the way; thenflip the handle
down to lock the dipstick in place.
How to Add Fluid
Refer to the Maintenance Schedule to determine what
kind of transmissionfluid to use. SeePart D:
Recommended Fluids and Lubricants on page 6-33.
Addfluid only after checking the transmissionfluid while
it is hot. (A cold check is used only as a reference.)
If thefluid level is low, add only enough of the proper
fluid to bring the level up to the HOT area for a hot
check. It doesn’t take muchfluid, generally less
than one pint (0.5 L). Don’t overfill.
Notice:We recommend you use onlyuid labeled
DEXRON
®-III, becauseuid with that label is
made especially for your automatic transmission.
Damage caused byuid other than DEXRON
®-III is
not covered by your new vehicle warranty.
•After addingfluid, recheck thefluid level as
described under“How to Check”earlier.
•When the correctfluid level is obtained, push the
dipstick back in all the way; thenflip the handle
down to lock the dipstick in place.
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How to Add Fluid
Here’s how to addfluid. Refer to the Maintenance
Schedule to determine what kind offluid to use.
SeePart D: Recommended Fluids and Lubricants on
page 6-33.
1. Remove thefiller plug.
2. Addfluid at thefiller plug hole. Add only enough
fluid to bring thefluid level up to the bottom of the
filler plug hole.
3. Install thefiller plug. Be sure the plug is fully
seated.
Hydraulic Clutch
The hydraulic clutch linkage in your vehicle is
self-adjusting. The clutch master cylinder reservoir is
filled with hydraulic clutchfluid.
It is not necessary to regularly check clutchfluid unless
you suspect there is a leak in the system. Adding
fluid won’t correct a leak.
Afluid loss in this system could indicate a problem.
Have the system inspected and repaired.
When to Check and What to Use
Refer to the Maintenance Schedule to determine how
often you should check thefluid level in your clutch
master cylinder reservoir and for the properfluid.
SeePart B: Owner Checks and Services on page 6-26
andPart D: Recommended Fluids and Lubricants
on page 6-33.
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